Re: hfs breakage

[Bean]

On Jan 16, 2008 8:38 AM, Pavel Roskin <address@hidden> wrote:
> Hello!
>
> I have noticed that GRUB won't list all files on the boot partition of
> my PowerMAC.  I can still get the full list if I mount the partition in
> Linux of use hfsutils.
>
> I put the image here:
> http://red-bean.com/proski/sda2.img.bz2
>
> It's just 210k compressed.  The problem can be reproduced on any
> ordinary PC.  Just uncompress the image and create a file called
> device.map with the following contents:
>
> (hd0) sda2.img
>
> Compile grub with grub-emu support:
>
> ./configure --enable-grub-emu && make
>
> Run grub-emu:
>
> grub-emu -m device.map -r hd0
>
> grub> ls (hd0)/
> acorn.mod affs.mod amiga.mod apple.mod blocklist.mod boot.mod cat.mod
> cmp.mod configfile.mod cpio.mod elf.mod ext2.mod fat.mod font.mod
> fshelp.mod gpt.mod grub
> grub>
>
> Files after "grub" are not shown.
>
> I have already considered the possibility that having files with similar
> names "grub" and "grub.cfg" may be a problem.  But renaming "grub" to
> "gurb" makes no difference.
>
> I have been rewriting the file called "grub" many times, so maybe it was
> moved to some additional leaf of the directory tree, confusing the hfs
> implementation in GRUB (I'm just guessing, I don't know anything about
> hfs).
>
> Moreover, if I mount the image as loop in Linux and remove files "grub"
> and "grub.cfg", "ls" in grub-emu will go into infinite loop and print
> "ofboot.b pc.mod raid.mod reboot.mod reiserfs.mod search.mod sfs.mod
> sun.mod suspend.mod terminal.mod" over and over again.

I think i figure out the problem, please try the following patch.

        * fs/hfs.c : Add magic values for cnid
        (grub_hfs_iterate_records): Use the correct file number for extents
and catalog file. Fix problem in next index calculation.
        (grub_hfs_find_node): Replace recursive function call with loop.
        (grub_hfs_iterate_dir): Replace recursive function call with loop.
        

diff --git a/fs/hfs.c b/fs/hfs.c
index e8e9c3e..3480d3e 100644
--- a/fs/hfs.c
+++ b/fs/hfs.c
@@ -43,6 +43,16 @@ enum
     GRUB_HFS_FILETYPE_FILE = 2
   };

+/* Catalog node ID (CNID).  */
+enum
+  {
+    GRUB_HFS_CNID_ROOT_PARENT = 1,
+    GRUB_HFS_CNID_ROOT = 2,
+    GRUB_HFS_CNID_EXT = 3,
+    GRUB_HFS_CNID_CAT = 4,
+    GRUB_HFS_CNID_BAD = 5
+  };
+
 /* A node descriptor.  This is the header of every node.  */
 struct grub_hfs_node
 {
@@ -447,7 +457,8 @@ grub_hfs_iterate_records (struct grub_hfs_data
*data, int type, int idx,

       /* Read the node into memory.  */
       blk = grub_hfs_block (data, dat,
-                           0, idx / (data->blksz / nodesize), 0);
+                            (type == 0) ? GRUB_HFS_CNID_CAT :
GRUB_HFS_CNID_EXT,
+                           idx / (data->blksz / nodesize), 0);
       blk += (idx % (data->blksz / nodesize));
       if (grub_errno)
        return grub_errno;
@@ -481,10 +492,7 @@ grub_hfs_iterate_records (struct grub_hfs_data
*data, int type, int idx,
            return 0;
        }

-      if (idx % (data->blksz / nodesize) == 0)
-       idx = grub_be_to_cpu32 (node.node.next);
-      else
-       idx++;
+      idx = grub_be_to_cpu32 (node.node.next);
     } while (idx && this);

   return 0;
@@ -501,6 +509,7 @@ grub_hfs_find_node (struct grub_hfs_data *data, char *key,
 {
   int found = -1;
   int isleaf = 0;
+  int done = 0;

   auto int node_found (struct grub_hfs_node *, struct grub_hfs_record *);

@@ -532,6 +541,8 @@ grub_hfs_find_node (struct grub_hfs_data *data, char *key,
          /* Found it!!!!  */
          if (cmp == 0)
            {
+              done = 1;
+
              grub_memcpy (datar, rec->data,
                           rec->datalen < datalen ? rec->datalen : datalen);
              return 1;
@@ -541,16 +552,20 @@ grub_hfs_find_node (struct grub_hfs_data *data, char *key,
       return 0;
     }

-  if (grub_hfs_iterate_records (data, type, idx, 0, node_found))
-    return 0;
+  do
+    {
+      found = -1;
+
+      if (grub_hfs_iterate_records (data, type, idx, 0, node_found))
+        return 0;

-  if (found == -1)
-    return 0;
+      if (found == -1)
+        return 0;

-  if (isleaf)
-    return 1;
+      idx = found;
+    } while (! isleaf);

-  return grub_hfs_find_node (data, key, found, type, datar, datalen);
+  return done;
 }


@@ -607,21 +622,23 @@ grub_hfs_iterate_dir (struct grub_hfs_data
*data, grub_uint32_t root_idx,
       return hook (rec);
     }

-  if (grub_hfs_iterate_records (data, 0, root_idx, 0, node_found))
-    return grub_errno;
+  do
+    {
+      found = -1;
+
+      if (grub_hfs_iterate_records (data, 0, root_idx, 0, node_found))
+        return grub_errno;

-  if (found == -1)
-    return 0;
+      if (found == -1)
+        return 0;

+      root_idx = found;
+    } while (! isleaf);
+
   /* If there was a matching record in this leaf node, continue the
      iteration until the last record was found.  */
-  if (isleaf)
-    {
-      grub_hfs_iterate_records (data, 0, next, 1, it_dir);
-      return grub_errno;
-    }
-
-  return grub_hfs_iterate_dir (data, found, dir, hook);
+  grub_hfs_iterate_records (data, 0, next, 1, it_dir);
+  return grub_errno;
 }


-- 
Bean